Chemistry

The knowledgebase of the American Chemical Society - one of the most powerful knowledgebases in the world.
CAS SciFinder-n includes new features like AI-powered relevance sorting, relevance-ranked results, citation mapping, biosequence searching, retrosynthetic analysis, patent landscape mapping, touch-screen enabled structure drawing and more.
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Science Citation Index is a multidisciplinary index to the journal literature of the sciences.

Very Short Introductions provide intelligent and serious introductions to a huge range of subjects, written by experts in the field who combine facts, analysis, new ideas, and enthusiasm to make challenging topics highly readable.